1. Technical Field
The present disclosure relates to electrode slurries and electrodes and, particularly, to electrode slurries of lithium batteries and electrodes of lithium batteries.
2. Description of Related Art
A lithium battery includes a negative electrode (i.e., anode), a positive electrode (i.e., cathode), a separator located between the anode and the cathode, and an electrolyte solution soaking the anode, the cathode and the separator. In order to form a cathode, cathode slurry including a lithium-transition metal oxide as a cathode active material, carbon black as a conductive agent, polyvinylidene fluoride (PVDF), or styrene-butadiene rubber (SBR) as a binder and N-methyl-2-pyrrolidone (NMP) as a solvent is prepared. The cathode slurry is coated on a collector made of a metal foil, and then drying, pressing, and molding steps are performed. In order to form an anode, the same method as described above is performed, except that the anode slurry includes carbon or carbon composite capable of lithium ion intercalation/deintercalation as an anode active material, PVDF or SBR as a binder and NMP as a solvent are used. The slurry plays an important role to the manufacturing process of the electrodes, and performance of the electrodes and lithium batteries.
However, although the slurries include the same components, the performance of the lithium batteries using them may be different. For example, if the sequence of adding the components is different, the rate performance of the lithium batteries may be different. This may be caused by nonuniform dispersion of the conductive agent in the slurry. To resolve this problem, a polymer type dispersant agent may be added into the slurry. The polymer type dispersant agent may include a polymer backbone capable of surface-adsorption and a side-chain having non-ionic surfactant properties. However, the polymer type dispersant agent may have a greater effect on the slurry using water based solvent than the slurry using oil based solvent such as NMP, caused by its own dispersing problem and high viscosity.
What is needed, therefore, is to provide an electrode slurry using oil based solvent having good performance to the electrode, and the electrode formed from the slurry.